Parameter Optimization in Sleep Apnea Treatment Apparatus

ABSTRACT

The present invention includes a method and apparatus for the optimized treatment of obstructive sleep apnea. The present invention includes a pressure source configured to provide positive airway pressure to a patient who is resting at home. The pressure source receives control signals from control electronics that define a pressure profile to be delivered to the patient. The control electronics select parameters to define the pressure profile based on factors such as a user selection, information received from a sensor, and/or a prescription.

RELATED APPLICATIONS

This non-provisional application is a continuation of U.S.Non-Provisional Application Ser. No. 11/224,548 entitled “ParameterOptimization in a Sleep Apnea Treatment Apparatus”, filed Sep. 12, 2005.U.S. Non-Provisional Application Ser. No. 11/224,548 claims priority toU.S. Provisional Application Ser. No. 60/609,897, Entitled “ParameterOptimization in a Sleep Apnea Treatment Apparatus” by Winthrop D.Childers and Ruth O. Childers, filed on Sep. 14, 2004, incorporatedherein by reference under the benefit of U.S.C. 119(e).

FIELD OF THE INVENTION

The present invention relates to the treatment of sleep disorders. Moreparticularly, the present invention relates to a method and apparatusfor optimizing the treatment of obstructive sleep apnea.

BACKGROUND

OSA (obstructive sleep apnea) is a disease that adversely affects anestimated more than 10 million adults in the United States alone. Thedisorder manifests itself when a person has repeated trouble breathingat night. The trouble breathing results from a collapse and henceobstruction of the pharynx (throat air passage). When this occurs, atthe least it disturbs sleep but can also cause cardiac arrest. Those whosuffer from OSA tend to have excessive daytime sleepiness, which canlead to lost productivity and accidents.

The best method for treating OSA is with a device that provides PAP(positive airway pressure) to a patient at night. The patient typicallywears a mask such as a mask that fits over the nose. The mask ispressurized with a gas such as air that is maintained a positive gaugepressure that may be in the range of 5 to 25 cm of water. The positivepressure applied to the nose will tend to prevent obstruction bydistending the collapsible throat air passage.

The most general form of PAP is CPAP, or continuous positive airwaypressure. This is effective, but it can have some drawbacks. For somepatients with weakened pulmonary systems, breathing in and out withconstant pressure may be labored. For those patients in particular PAPsystems that provide variation in pressure that is timed with the cycleof breathing is preferred. This application of pressure is referred toas IPAP (inspiratory positive airway pressure) and EPAP (expiratorypositive airway pressure).

Historically OSA has been treated in sleep clinics where the OSA problemcan be diagnosed and treated. This tends to be quite expensive,impractical, and uncomfortable. To address these issues, PAP deviceshave been designed for the home. The devices are relatively inexpensive;in fact, one such device may cost less than spending a few days in asleep clinic. But along with a great benefit, sending such devices homewith patients creates some new issues.

Such issues with take-home PAP systems have to do withpatient-to-patient variations and with variations in a particularpatient's condition. Historically the proper settings for a PAP deviceneed to be determined in a sleep clinic. This is very expensive andprobably impractical given the number of those victimized by OSA. Inaddition, when a patient has time-based variations this cannot beproperly addressed by a sleep clinic. There is a need for a take homePAP apparatus that can address these patient to patient and time basedvariations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a PAP (positive airway pressure)treatment apparatus of the present invention.

FIG. 2 is a schematic block diagram of a PAP (positive airway pressure)treatment apparatus of the present invention.

FIG. 3 is a schematic block diagram of a PAP (positive airway pressure)treatment apparatus of the present invention.

FIG. 4 a is an illustration of a portion of a user interface utilized inthe PAP (positive airway pressure) treatment apparatus of the presentinvention for selecting an operating mode.

FIG. 4 b is an illustration of a portion of a user interface utilized inthe PAP (positive airway pressure) treatment apparatus of the presentinvention during operation.

FIG. 5 is a flow chart representation of a method whereby the PAP of thepresent invention selects between standard and custom operating modes.

FIG. 6 is a flow chart representation of a method whereby the PAP of thepresent invention is operated in a way that is optimal either for along-term condition or a transient condition of a patient.

FIG. 7 is a flow chart representation of a method whereby the PAP of thepresent invention is receives updated operating parameters from aprescription.

FIG. 8 is a flow chart representation of a method whereby the PAP of thepresent invention generates new custom operating parameters based onanalyzing information based on an acoustic signal monitored in the mask.

FIG. 9 is a flow chart representation of a method whereby the PAP of thepresent invention generates new custom operating parameters based onanalyzing information based on an acoustic signal monitored in the mask.

FIG. 9 a depicts an initial pressure versus time profile whichcorresponds to element 118 of FIG. 9.

FIG. 9 b depicts an incident pressure versus time profile whichcorresponds to element 122 of FIG. 9.

FIG. 9 c depicts a third pressure profile which corresponds to element126 of FIG. 9.

FIG. 10 is a flow chart representation of a method whereby the PAP ofthe present invention utilizes information from an external sensor toderive a more accurate representation of acoustic noises generatedinternal to a patient's respiratory system.

FIG. 11 is a flow chart representation of a method whereby the PAP ofthe present invention generates and compares a digital signaturerepresentation of an acoustic noise pattern over time versus aninternally stored digital signature.

FIG. 12 is a flow chart representation of a method whereby the PAP ofthe present invention utilizes analysis of sounds inside the mask todetermine whether a transient condition is present and to utilizeparameters consistent with the determination.

FIG. 13 is a flow chart representation of a method whereby the PAP ofthe present invention determines whether an insufficient operatingmargin requires a new prescription.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is a PAP (positive airway pressure) apparatusconfigured for use in the home and suitable for treatment of OSA(obstructive sleep apnea). A PAP device of the present invention can bea CPAP (continuous positive airway pressure) device or an IPAP/EPAP(inspiratory positive airway pressure/expiratory positive airwaypressure) device. The PAP of the present invention operates or provides“treatment cycles” in multiple modes including a “standard” modegoverned by a “standard” set of operating parameters and a “custom” modegoverned by a “custom” set of operating parameters. A “treatment cycle”is essentially the complete cycle of “pressure profiles” provided to apatient during a sleep cycle. An example of a “treatment cycle” isdiscussed with respect to FIG. 9. A “pressure profile” is a pressureversus time applied by the PAP device. Examples of pressure profiles aredescribed with respect to FIGS. 9, 9 a, 9 b, and 9 c.

The PAP apparatus of the present invention includes a mask that iscoupled to a controllable pressure source under control of controlelectronics. The control electronics are coupled to an informationstorage device and to an input selection device. The information storagedevice stores information indicative of the operating parameters. Fromhere forward, when we say that the information storage devices “stores”parameters, we mean that the device stores information indicative of theparameters that can be utilized by the control electronics to causeoperation of the pressure source that is consistent with the parameters.

The operating parameters include “variable” parameters that can becustomized according to the needs of a patient. The information storagedevice provides storage for redundant values for each of the variableparameters. Thus, for each variable parameter, a “standard version” isstored and one or more “custom versions” are stored. The controller isconfigured to operate in a “standard” mode when it utilizes a set ofstandard parameters and to operate in a custom mode when it utilizes aset of custom parameters.

The controller selects an operating mode in response to a mode signalfrom the input selection device. When the mode signal is received, thecontroller then loads and/or utilizes a set of parameters for theparticular mode selected. The mode may be customized according to theparticular patient's intermediate or long term therapeutic needs.Alternatively, the mode may be selected in response to a shorter termtransient condition of the patient.

A PAP treatment apparatus 2 configured for home based treatment of sleepapnea is depicted schematically in FIG. 1 and in schematic block diagramform in FIG. 2. The treatment apparatus 2 includes a pressure source 4that is fluidically coupled to a mask 6 via a conduit 8. In oneembodiment, the pressure source 4 includes a blower 10 and a pressuremodulator 12. During use a patient wears mask 6. PAP treatment apparatusapplies positive pressure to the mask via the pressure source 4. In theembodiment wherein the pressure source 4 includes blower 10 and pressuremodulator 12, the pressure modulator 12 enhances the speed of responseand accuracy of the pressure source 4.

The PAP treatment apparatus 2 includes a controller 14 that is coupledto a sensor 16, an information storage device 18, an input selectiondevice 20, user interface 21, and the pressure source 4. In someembodiments, input selection device is a portion of user interface 21.The controller 14 receives inputs from sensor 16, information storagedevice 18, input selection device 20, and in provides control signals topressure source 4.

The information storage device stores information indicative ofoperating parameters for operating the pressure source 4. The operatingparameters include fixed operating parameters that do not vary accordingto a particular operating mode and variable operating parameters that dovary according to a particular operating mode.

The information storage device stores first or standard operatingparameter information 22 and second or custom operating parameterinformation 24 for each of the variable operating parameters. Thestandard operating parameter information 22 defines a first or standardoperating mode for PAP treatment apparatus 2. The custom operatingparameter information 24 defines a second or custom operating mode forPAP treatment apparatus 2.

The controller receives a mode selection from inputs selection device 20and operates PAP treatment apparatus in a manner consistent with themode selected. If a first or standard mode is selected, then controller14 utilizes standard parameters 22. If a second or custom mode isselected, then controller 14 utilizes custom parameters 24.

An exemplary PAP treatment apparatus 2 is depicted in more detailedblock diagram form in FIG. 3. In the exemplary embodiment, air isreceived by inlet filter 26 which passes filtered air to an intake ofpressure generator 10. Pressure generator 10 supplies pressurized air toan air manifold 30 that “warehouses” pressurized air. Manifold 30 passesair to conduit 32 via valve 34. Together manifold 30 and valve 34operate together as modulator 12. Finally, conduit 32 providespressurized air to mask 6 worn by the patient. In this embodiment, themanifold 30 is maintained at a higher gauge pressure than conduit 32under control of controller 14.

Controller or control electronics 14 is coupled to information storagedevice 18, input selection device 20, pressure generator 10, valve 34,acoustic sensor or microphone 16, conduit sensor 38, pressure sensor 40,external sensor 42, and aerosol generation device 44. Similar to theembodiment discussed with respect to FIGS. 1 and 2, information storagedevice 18 stores variable operating parameters that includes a first orstandard set of operating parameters and a second or custom set ofoperating parameters. The controller 14 is configured to receive aninstruction from the input selection device 20 and in response tooperate pressure generator 10 and pressure modulator 12 using theselected operating parameters.

The input selection device 20 is configured to impart a signal tocontroller 14 indicative of one or more operating modes for controller14. An appropriate input selection device can take on any number offorms including a memory card, flash memory, a user selected switch, andLCD touch screen interface, a wireless link, a sensor signal, a“fire-wire” or USB link, an RFID device input, or any other input devicethat is capable of imparting a signal to controller 14 indicative of anoperating mode.

Based upon a mode selected via input selection device 18, controller 14selects operating parameters that define operation of the PAP treatmentdevice 2 for a treatment cycle. Operating parameters include appliedpressure profiles, therapeutic pressure levels, a maximum pressurelevel, aerosol parameters, and other factors that may be important for agiven patient condition. A pressure profile defines a pressure versustime curve to be applied to mask 6. A therapeutic pressure level definesa pressure applied to mask 6 intended to open or prevent obstruction ofthe throat air passage. A maximum pressure level defines an upper limitfor air pressure to be applied to mask 6. Finally aerosol parametersdefine operating instructions for aerosol generation device 44.

Controller 14 receives signals from one of mask sensors 16 such as amicrophone 16 that can be indicative of an obstructive event. Controller14 also receives information from an external sensor 42 that can be amicrophone external to mask 6. Controller 14 can utilize informationfrom the external sensor 42 to subtract our or compensate for noisesexternal to mask 6. Controller 14 utilizes information received inputselection device 20, information storage device 18, microphone 16, andexternal sensor 42 to select a pressure profile applied to mask 6 and tooperate aerosol generation device 44.

The pressure profile applied to mask 6 can be rapidly and preciselymodulated via a pressure control system that includes pressure generator10 and pressure modulator 12. Pressure modulator 12 includes manifold 30and valve 34 under control of controller 14. Controller 14 receives asignal from pressure sensor 40 that is indicative of a manifold pressurelevel in manifold 30. In the example wherein pressure generator 10 is afan, the controller 14 adjusts a fan speed to maintain the pressure inmanifold 30 within a desired pressure range. Controller 14 receives asignal from a sensor 38 in conduit 8 and/or mask 6 that is indicative ofthe pressure level in conduit 8. Controller opens and closes valve 34 tomaintain a desired pressure range in mask 6. The use of a manifold 30and valve 34 to regulate pressure in mask 6 allows controller 14 to veryprecisely and rapidly modulate pressure in mask 6. This is particularlyimportant for IPAP/EPAP systems or where a rapid response to anobstructive event is required. In order for the mask pressure to beproperly controlled and for rapid responses, the pressure in manifold 30is maintained at a level above the anticipated required pressure rangesfor mask 6.

FIGS. 4 a and 4 b depict an exemplary user interface 21 for PAPapparatus 2 including a backlit LCD (liquid crystal display) or OLED(organic light emitting diode) touch screen 46. FIG. 4 a depicts a viewdisplayed by screen 46 used to select an operating mode for PAPapparatus 2 and FIG. 4 b depicts a view displayed by screen 46 duringoperation. According to FIG. 4 a, the operating modes include a standardoperating mode that is selected via a top button 48 that would activatethe “defaults” for apparatus 2.

By selecting button 50, a “custom” mode can be selected that utilizesoperating parameters that have been customized and optimized for theparticular patient using PAP apparatus 2. This mode may have one or moreparticular pressure profiles (defined pressure versus time that isapplied to mask 6) that is/are more comfortable or effective for theparticular patient.

By selecting button 52, parameters indicative of a prescription may beutilized. For example a prescription may have been provided that allowsfor a higher maximum therapeutic pressure than the standard operatingmode would allow.

By selecting button 54, parameters indicative of a transient conditionsuch as a cold congestion can be utilized. For example, selecting button54 may activate aerosol device 44 and it may provide a pressure profilethat is effective for the particular transient condition.

By selecting button 56, the aerosol device 44 may emit a medicatedaerosol. In the illustrated example, buttons 50-56 may be individuallyselected or all selected at once if there are various customizationsand/or transient conditions required for the operation of sleep apneatherapy device 2.

After the “START” 58 button is selected, apparatus 2 begins operatingand then displays a screen according to FIG. 4 b that indicates selectedsettings and a condition of filter 26. According to FIG. 4 b, the filterhas 9% of its expected life remaining and a “WARNING” indicator isdisplayed to alert the user that the filter is in need of replacement.

An exemplary operation of PAP treatment apparatus is depicted in FIG. 5.According to 60, parameters are stored on information storage device 18including standard parameters 22 indicative of a “standard” operatingmode and custom parameters 24 indicative of a “custom” operating mode.According to 62, the apnea treatment apparatus 2 configured for home useis provided to the patient. In one embodiment, 60 can occur before62—apparatus 2 can be provided to the patient with the parametersalready loaded. Alternatively, 62 can occur before 60.

According to 64, an input selection indicative of a standard operatingmode or a custom operating mode is imparted to controller 14 via inputselection device 20. According to 66, a decision is made by controller14 depending upon whether the standard or custom mode is selected. Ifthe standard mode is selected then controller selects standardparameters 22 according to 68 and operates apparatus 2 according to thestandard parameters 22 according to 70. If the custom mode is selected,then the controller selects custom parameters 24 according to 72 andoperates the apparatus using the custom parameters 24 according to 74.

An exemplary embodiment of the operation of PAP apparatus 2 for treatinga transient condition is depicted with respect to FIG. 6. According to76 a sleep apnea treatment apparatus 2 configured for home use isprovided to a patient. According to 78, the patient makes a selectionusing input selection device 20 to operate the device according to along-term condition or a transient condition. Stated another way, theuser either selects a first operating mode whose variable operatingparameters are more optimal for a long-term condition or a secondoperating mode whose variable operating parameters are more optimal fora transient condition (such as congestion resulting from a viralinfection).

A decision 80 is made based on the selection. According to 82, if thelong-term or first mode is selected, then treatment apparatus 2 isoperated according to long-term optimized parameters. According to 84,if the transient or second operating mode is selected, then apparatus 2is operated utilizing transient operating mode parameters. These mayinclude, for example, increased breathing assistance pressures or thelike for example to offset nasal congestion. According to 86, theseparameters may also include inputting medicated aerosol into conduit 8and hence to mask 6. The medicated aerosol may be generated by aerosolgeneration device 44.

Another exemplary embodiment of the operation of PAP apparatus 2 updatedby a prescription is depicted with respect to FIG. 7. According to 88, apatient receives a prescription that defines operating parameters fortreatment apparatus 2. An example of such an operating parameter mightbe the maximum operating pressure. This typically will be in the 8-20 cmof water (positive gauge pressure) range in the “default” or standardcase. For some patients, the required maximum therapeutic pressure maybe greater than 20 cm of water for example.

Other possible parameters by prescription 88 might include: (1) thedispensing of aerosolized medicants for the purpose of clearing atransient congestion problem, or (2) other operational aspects like atime-pressure integral factor. According to 90, the prescriptionoperating parameter information that is usable by apparatus 2 isgenerated or derived from the prescription.

Then according to 92, the information is transferred to the informationstorage device 18. This can be done any number of ways. For example, aphysician may have a computer for storing prescription or operatingparameter information on a flash memory card. Alternatively, the doctormay authorize a separate entity (such a as a service provider) toprovide a memory device, an internet transmission, or some other meansof providing the proper operating parameters to the information storagedevice 18.

According to 94, the controller 14 receives an input from selectiondevice that is indicative of the prescription. This could be a userselection from a menu as depicted in FIGS. 4 a/b, or it could be the actof plugging in a memory card storing the parameters.

According to 96 and 98, the control electronics then load theprescription operating parameter information and operate treatmentapparatus 2 pursuant to the prescription operating parameterinformation.

An exemplary embodiment of the operation of apnea treatment apparatus isdepicted with respect to FIG. 8 wherein the treatment apparatusgenerates a custom set of operating parameters as a result of analyzingoperational results during a treatment. According to 100 an apneatreatment apparatus 2 configured for home use is provided to a patient.

According to 102 and 104, the controller 14 reads operating parameterinformation parameter information from the information storage device 18and operates the treatment apparatus applying a pressure versus time tomask 6 pursuant to the operating parameter information read according to102. According to 106, the controller 14 monitors a signal received frommicrophone 16 that is indicative of a sound intensity versus time inmask 6. According to 108 the controller then derives resultinginformation indicative sound intensity versus time.

According to 110, the controller 14 analyzes the resulting informationin order to generate or compute a new custom set of operatingparameters. According to 112, the new custom set of operating parametersis then stored on the information storage device.

A specific treatment cycle that is similar to that depicted with respectto FIG. 8 is now depicted with respect to FIG. 9 in flow chart form.According to 114, operating parameter information is provided frominformation storage device 18 to controller 14. According to 116 asignal is monitored that is indicative of sounds reaching mask 6. Thesignal is derived from microphone 16. According to 118, a first orinitial pressure profile 118 is applied to mask 6. The first pressureprofile is defined by the operating parameters provided according to 114and is an initial applied pressure versus time profile.

An exemplary first pressure profile 118 is the initial pressure versustime profile depicted with respect to FIG. 9 a. When the patient isfirst falling asleep, a comfortable first pressure P1 is applied to mask6 according to portion 118 a of profile 118 between times t1 and t2.First pressure P1 may, for example, be in the range of 0 to 4 cm ofwater positive gauge pressure. After allowing time to fall asleep, thepressure then ramps up according to portion 118 b of profile 118 betweentimes t2 and t3. Finally, the pressure level reaches a second pressureP2 that may be in the range of 3 to 8 cm of water for example and thispressure P2 is maintained at a constant level during portion 118 c ofprofile 118. Pressure levels P1 and P1, the slope between time t2 andt3, as well as the time durations of portions 118 a, 118 b, and 118 care each defined by the parameters provided according to 114 in thisexample.

Variations are possible as FIG. 9 a is for illustrative purposes only.For example pressure versus time curve 118 may be non-linear, or mayhave multiple flat and sloped portions. The parameters loaded accordingto 114 define portions of curve 118 individually, or else a singleparameter may define the entire curve according to a lookup table. Thelookup table in this case would have pressure versus time informationfor controlling the pressure in mask 6 and a single parameter may selectdifferent curves. Also, the magnitude of pressures P1 and P2 may varymarkedly depending on the needs of the patient.

According to 120, a decision is made by controller—has a soundindicative of an obstructive event (snoring and/or breathing difficulty)been sensed? If the answer is no, that no event has been sensed, thenthe profile according to 118 continues. Process 120 may be executedduring or after the profile defined by 118 is being executed. If theanswer is yes, and an obstructive event is sensed, then a secondpressure profile is applied to mask 6 according to 122. The secondprofile is referred to as an “incident profile” and defines a steep orrapid pressure versus time ramp to aggressively eliminate theobstructive event.

An exemplary embodiment of the second pressure profile 122 isillustrated with respect to FIG. 9 b. During a first portion 122 a ofprofile 122, the pressure is rapidly ramping from an initial pressure P3to a therapeutic pressure P4 while a time progresses from t5 to t6.Pressure P3 may equal pressure P2 in some cases, particularly if firstpressure profile 118 has reached pressure P2 before second pressureprofile 122 begins. A pressure P4 is reached at time t6. The slope ofthe pressure ramp defined by portion 122 a is defined by the parametersutilized according to step 114. Variations on profile 122 are possible.For example, the ramp may again be non-linear. It may be desirable tohave a steeper portion at the beginning of portion 122 a to minimize thetime required to eliminate the obstructive event. Also, the slope ofportion 122 a may be determined according to whether the obstructiveevent is only snoring versus being a dangerous throat obstruction.

While the pressure profile of 122 is being applied, the signalindicative of noise in mask 6 is being monitored. According to 124, asecond decision is made. If the obstructive event continues to besensed, then the second therapeutic profile 122 continues.

If, on the other hand, the obstructive event has stopped (as a result ofthe therapeutic profile), then a third pressure profile is appliedaccording to 126 wherein the applied pressure is gradually reduced. Anexemplary profile 126 is depicted with respect to FIG. 9 c. The pressureapplied to mask 6 ramps down from a higher pressure P6 to a lowerpressure P5 that may be equal to or a little higher than P2 duringsegment 126 a of profile 126. If no more obstructive events are sensed,the pressure be maintained at pressure level P5.

Note that the operating parameters generally define pressure levels P3,P4, P5, and P6. An exception to this would be if a change is sensedbefore a pressure ramp ends. For example, if according to 124 theobstructive event is no longer sensed before segment 122 a is reaches amaximum therapeutic pressure then pressure P4 will be determined by thepressure ramp and the pressure P3 for example. Note that while the flowchart depiction of FIG. 9 has “steps” such as steps 118 and 120, it isto be understand that these steps may overlap in time since sensing achange such as a new obstruction may interrupt the pressure profile ofthe previous step.

According to 128, information indicative of the obstructive event isstored. According to 130, the information from 128 is analyzed and a newset of custom operating parameters is generated in response. Followingare some examples of the new set of custom operating parameters thatmight be generated.

As a first example, one or more new a parameters may define a newinitial pressure profile 118 as applied in step 118. From analyzing theobstructive events, the controller 14 may determine that the initialprofile was insufficient to adequately reduce or prevent an obstructiveevent. Thus, for example the new initial pressure profile would rise toa higher initial operating pressure level P2. As other examples ofparametric changes, the time duration of segment 118 a may be changed orthe slope of segment 118 b may be changed.

As a second example, one or more new parameters may define a newincident pressure profile as applied in step 122. From analyzing acontinuation of the obstructive events, the controller 14 may determinethat the incident pressure profile does not rise aggressively enough toend the obstructive event soon enough. Thus, the slope of segment 122 amay be increased and perhaps a peak therapeutic pressure P4 may beincreased.

As a third example, one or more new parameters may define a new thirdpressure profile 126. For example, the final pressure P5 may beincreased or decreased.

It is possible that a maximum therapeutic pressure defined byinformation storage device 18 may not be sufficient to effectively endobstructive events. If that is the case, then step 124 will continue todetermine that an obstructive event is occurring event when the highestpossible level of pressure P4 (same as the maximum allowed therapeuticpressure) has been reached. In that case therapy device 2 will providean alarm or other indication that a new prescription is required. Anexemplary method for providing such a new prescription is furtherdiscussed with respect to FIG. 13.

An operating method utilizing an external sensor such as a secondmicrophone 42 is depicted with respect to FIG. 10. According to step132, an apnea treatment apparatus 2 configured for home use is providedto a patient. According to step 134, the apparatus is operated accordingto operating parameters stored on information storage device 18.According to step 136, a signal from microphone 16 internal to mask 6 ismonitored. According to step 138, a signal from microphone 42 externalto mask 6 is monitored. According to step 140, the controller 14analyzes the signals from 136 and 138 and then generates correctedinformation indicative of sound being generated inside mask 6. This canbe used to reduce the effects of noises external to the mask 6 andrespiratory system of the patient who is wearing mask 6.

An operating method utilizing a digital signature is depicted withrespect to FIG. 11. The analysis of waveforms to generate “digitalsignatures” is known. For example, digital signature methodology isutilized to determine authenticity of signatures by comparing Fouriertransforms of the signature curve for example.

According to 142, a sleep apnea treatment apparatus 2 configured forhome use is provided to a patient. Sequence 143 includes steps 144-146and is performed during a first treatment cycle using apparatus 2.According to 144, a signal indicative of a sound in mask 6 versus timeis monitored. According to 145, the signal is analyzed to generate afirst digital signature. The first digital signature is then stored oninformation storage device 18 according to 146.

Sequence 147 includes steps 148-152 and is performed during a subsequentsecond treatment cycle using apparatus 2. According to 148, a secondsignal indicative of a sound in mask 6 versus time is monitored.According to 149, the second signal is analyzed to generate a seconddigital signature. According to 150, the first and second digitalsignatures are compared so as to determine a match. If a match isdetermined, then customized operating parameters may be utilized tocontrol apparatus 2 according to 152.

The digital signature may be utilized to verify an identity or conditionof a particular patient. For example, during step 146, the controller 14may store information on information storage device indicative ofcertain operating parameters that are specific to treating a conditionimplied by the first digital signature.

An operating method that is a hybrid between the operating methods ofFIGS. 6 and 8 is depicted with respect to FIG. 12. According to 154, PAPtreatment device 2 is operated according to operating parameters storedon information storage device 18. According to 156, a signal derivedfrom one or more of sensors 16 or 38 is monitored. According to 158, thesignal is analyzed to determine whether characteristics of the signalindicative of a transient condition are present. The controller, inresponse to this analysis, generates a decision according to 160. If theanalysis indicates no transient condition, apparatus 2 is operated usinglong term optimized operating parameters according to 162. If, however,a transient condition is detected, then the device is operated accordingto 164 wherein operating parameters optimized for the transientcondition are utilized. One clear example of this operation is the casewhere congestion is detected (as would be evidence with a sounds orpressures indicative of congestion).

As an example of how this might be determined, congestion would tend toreduce a patient's ability to breath through the nose. This could bedetected by detecting a reduced breath-imparted flow rate throughconduit 8. This would indicate a condition requiring a decongestantand/or an increased flow rate of an aerosol from aerosol generator 44.Thus, 164 would include activating or increasing the activation ofaerosol generation device 44.

As another example of 164, the PAP therapy device may provide increasedbreathing assistance in the event that breathing difficulties aredetected.

An operating method for determining if the available pressure range issufficient is depicted in flow chart form with respect to FIG. 13.According to 166, a PAP therapy apparatus 2 is provided to a patient forhome use. According to 168, the therapy apparatus is operated consistentwith parameters stored on information storage device 18. The parametersinclude an upper limit defined for an applied therapeutic pressurelevel. According to 170, a signal indicative of sound intensity versustime in mask 6 is monitored using sensor 16. As a result of an analysis,a decision is made according to 172—is there a sufficient parametricoperating margin?

The parametric operating margin is defined as the difference between themaximum values for the operating parameters and those required toprevent or eliminate obstructive events during operating of treatmentapparatus 2. An example of how these parameters are applied is describedwith respect to FIG. 9. An example of an operating parameter is themaximum pressure level. If the required pressure for treating anobstructive event is close to or exceeds the maximum allowed pressure,then the parametric operating margin is insufficient.

According to 174, if the parametric operating margin is sufficient, thenthe current prescribed parameter limits (such as maximum pressure level,pressure ramp rates, etc.) are sufficient. If the parametric operatingmargin is not sufficient, then an indication is provided that a newprescription is required according to 176. This could take the form ofan alarm provided to the patient to let the patient know that aprescription is required via user interface 21. In another embodiment, aweb-enabled therapy device would directly contact the physician torequest an updated prescription.

The method depicted in FIG. 13 can be used in combination with themethods described with respect to FIG. 8 or FIG. 9. Following step 176,the methods of FIG. 7 can then be utilized to provide new prescriptioncontrol parameters to the information storage device 18.

While various methods have been depicted by flow charts 1-13, it is tobe understood that different elements or methods depicted by differentflow charts can be substituted or added from one flow chart to another.

1. An apparatus for treating sleep apnea of a patient comprising: an apparatus including a pressure source configured to be coupled to the airway of a patient during a treatment cycle; an information storage device configured to store information defining a plurality of different operating modes including a selected operating mode defining a selected pressure profile; a user interface configured to receive an input from a patient that activates the selected operating mode; and a controller configured to operate the pressure source using the selected pressure profile.
 2. The apparatus of claim 1 wherein the controller is configured to receive prescription operating parameter information and wherein the prescription operating parameter information defines the selected pressure profile.
 3. The apparatus of claim 1 wherein the selected operating mode defines an initial pressure profile and an incident pressure profile and wherein the controller is configured to operate the pressure source using the initial pressure profile before an obstructive event and to operate the pressure source using the incident pressure profile in response to an obstructive event.
 4. The apparatus of claim 3 wherein the user interface is configured to receive a selection from the patient modifying the initial pressure profile to provide a new initial pressure profile and wherein the controller is configured to operate the pressure source according to the new initial pressure profile during the treatment cycle before an obstructive event occurs.
 5. The apparatus of claim 1 further comprising a sensor apparatus configured to generate a signal during the treatment cycle and wherein the controller is configured to identify obstructive events based upon the signal and to store additional information based upon identifying the obstructive events.
 6. The apparatus of claim 5 wherein the controller is configured to define a new custom operating mode based upon the additional information.
 7. An apparatus for treating sleep apnea of a patient comprising: an apparatus including a pressure source configured to be coupled to the airway of a patient during a treatment cycle; an information storage device storing information defining an operating mode; a user interface configured to receive an input from the patient that defines a variable operating mode parameter; and a controller configured to: (1) read the selection from the patient that defines the variable operating mode parameter; and (2) operate the pressure source using the operating mode and according to variable operating mode parameter.
 8. The apparatus of claim 7 wherein the variable operating mode parameter defines an initial applied pressure versus time profile that is applied during the treatment cycle before an obstructive event occurs.
 9. The apparatus of claim 7 wherein the controller is configured to receive prescription operating parameter information and to store the prescription operating parameter information on the information storage device and wherein the prescription operating parameter information defines the operating mode.
 10. The apparatus of claim 7 further comprising a sensor apparatus configured to generate a signal during the treatment cycle and wherein the controller is further configured to: (1) analyze the signal to determine if the operating mode is sufficient to treat obstructive events; and (2) store information on the information storage device defining a new operating mode to replace the operating mode if the operating mode is not sufficient to treat obstructive events.
 11. The apparatus of claim 7 further comprising a sensor apparatus configured to generate a signal during the treatment cycle and wherein the controller is further configured to: (1) analyze the signal; (2) determine if there is sufficient operating margin provided by the operating mode based upon analyzing the signal; and (3) generate a warning if there is not sufficient operating margin provided by the pressure profile.
 12. The apparatus of claim 7 further comprising a sensor apparatus configured to generate a signal in response to obstructive events during the treatment cycle and wherein the controller is further configured to store a record indicative of obstructive events during the treatment cycle.
 13. An apparatus for treating sleep apnea of a patient comprising: an apparatus including a pressure source configured to be coupled to the airway of a patient during a treatment cycle; a sensor apparatus configured to generate a signal during the treatment cycle; an information storage device storing first information defining an operating mode that defines an initial pressure profile and an incident pressure profile; and a controller configured to: (1) read the first information defining the operating mode; (2) operate the pressure source to provide the initial pressure profile; (3) analyze the signal from the sensor apparatus during the treatment cycle; (4) identify an obstructive event based upon analyzing the signal; (5) operate the pressure source to provide the incident pressure profile in response to identifying the obstructive event; and (6) store second information on the information storage device as a result of analyzing the signal wherein the second information is indicative of whether a new operating mode is required.
 14. The apparatus of claim 13 wherein the second information defines new operating mode parameters defining a new pressure profile.
 15. The apparatus of claim 14 wherein the controller is configured to automatically operate the pressure source according to the new operating mode parameters.
 16. The apparatus of claim 14 wherein the controller is configured to automatically modify the incident pressure profile based upon the new operating mode parameters.
 17. The apparatus of claim 13 wherein the controller is configured generate a warning if the new operating mode is required.
 18. The apparatus of claim 13 wherein the controller is configured to receive prescription information that defines the first information.
 19. The apparatus of claim 13 further comprising a user interface configured to receive a selection from the patient that defines a modification to the initial pressure profile defining a new initial pressure profile and wherein the controller is configured to apply the new initial pressure according to step (2) of claim
 13. 20. The apparatus of claim 13 wherein the second information includes a record of obstructive events that occur during the treatment cycle. 